1. [Field of the Invention]
The present invention relates to a motor armature used in motors such as a brushless motor, a manufacturing method thereof and a motor.
2. [Prior Art]
Hitherto, as an armature used for a brushless motor and the like, there have been known one fabricated by winding a coil around an iron core made by laminating a plurality of punched steel plates or one fabricated by winding a coil around an iron core made by laminating a plurality of punched steel plates which are divided into a plurality of pieces and by cylindrically connecting each core around which the coil is wound.
However, the armature fabricated by winding the coil around the iron core made by laminating a plurality of punched steel plates has had problems that its overall structure is complicated in general and that it is difficult to wind the coil around the core.
Meanwhile, the armature fabricated by winding the coil around the iron core made by laminating a plurality of punched steel plates which are divided into a plurality of pieces and by cylindrically connecting each core around which the coil is wound has had a problem that although it is easy to wind the coil around the core, the assembly work thereof for connecting cylindrically each core piece around which the coil is wound is difficult.
Accordingly, it is a primary object of the present invention to provide a motor armature whose assembly work can be facilitated and which can be miniaturized and thinned.
A secondary object of the present invention is to provide manufacturing methods of the armature which facilitate and readily automate the assembly work.
In order to achieve the primary object, a motor armature of the present invention comprises a plurality of pole pieces in which a coil is wound around a rod made of a magnetic material; and a cylinder made of a magnetic material which is fixed with the plurality of pole pieces disposed radially at equal intervals at the position distant from the center by a predetermined distance on at least one side of the center side or the outer periphery side thereof.
The above-mentioned cylinder is formed by curling up a hoop member made of a magnetic material and the rod is a wire piece obtained by cutting a wire made of a magnetic material.
Because the armature of the present invention is simply constructed as described above, it allows the assembly works to be facilitated and the miniaturization, thinning and reduction of cost to be realized. Further, it allows to deal with changes in the size and structure of the armature readily and swiftly.
In order to achieve the secondary object, a method for manufacturing the inventive motor armature comprises a first step of creating a plurality of pole pieces in which a coil is wound around a wire piece 5 made of a magnetic material; a second step of fixing one end of the plurality of pole pieces created in the first step to one and the same plane of a hoop member made of a magnetic material at equal intervals; and a third step of creating a cylinder attached with pole pieces by curling up the hoop member to which the plurality of pole pieces are fixed in the second step so that the plurality of pole pieces come inside or outside.
Further, in parallel with creating the cylinder attached with the pole pieces by curling up the hoop member to which the plurality of pole pieces are attached so that the plurality of pole pieces come outside in the third step described above, an outer cylinder may be created while fixing each other end of the pole pieces with the hoop member.
Further, an inventive method for manufacturing the motor armature comprises a first step of creating a plurality of pole pieces in which a coil is wound around a wire piece made of a magnetic material; and a second step of fixing one end of the plurality of pole pieces created in the first step either to the inner peripheral face or the outer peripheral face of a cylinder formed by curling up a hoop member made of a magnetic material radially at equal intervals.
Further, in the second step described above, it is possible to arrange such that an outer cylinder coaxial with the cylinder attached with the pole pieces is fixed with other end of the plurality of pole pieces fixed to the cylinder attached with the pole pieces after creating the cylinder attached with the pole pieces by curling up the hoop member so that the plurality of pole pieces come outside.
Thus, the rod (wire piece) and the hoop members are used in the inventive method for manufacturing the armature. It then allows the automation to be facilitated and to deal with changes in the size and structure of the armature swiftly by changing the thickness of the wire piece and the thickness of the hoop member.